This information is about Ewing's sarcoma in children. It is helpful to read it alongside our general information on children's cancer, which contains more information about cancers in children, their diagnosis and treatment, and the support services available.

Sarcomas are rare types of cancer that develop in the supporting structures of the body. There are two main types: bone sarcomas and soft tissue sarcomas.

Bone sarcomas can develop in any of the bones of the skeleton, but may also develop in the soft tissue near bones.

Soft tissue sarcomas can develop in muscle, fat, blood vessels or any of the other tissues that support, surround and protect the organs of the body.

Ewing’s sarcoma is named after Dr James Ewing, who described the tumour in the 1920s. It is a cancer which can develop anywhere in the body, although it most often starts in the bone. Any bone can be affected, but the pelvis, thigh bone (femur) and shin bone (tibia) are the most common places.

Fewer than 30 children develop Ewing’s sarcoma each year in the UK. It usually occurs in the teenage years, and more commonly affects boys than girls.

Although Ewing's sarcoma is a type of bone cancer, it can also very rarely occur in the soft tissues rather than starting in the bone. This is called extraosseous Ewing's sarcoma. Sometimes these cancers are called primitive neuroectodermal tumours (PNET).

The exact causes of primary bone cancer are unknown. The development of Ewing's sarcoma may be related in some way to times of rapid bone growth, which may explain why more cases of Ewing's sarcoma are seen in teenagers. Like other cancers, it is not infectious and cannot be passed on to other people.

Pain is the most common symptom of bone cancer. However, symptoms may vary depending on the position in the body and the size of the cancer. There may be some swelling in the affected area and it may become tender to touch. Bone cancer is sometimes discovered when a bone that has been weakened by cancer breaks, after the child has a minor fall or accident.

A variety of tests and investigations may be needed to diagnose a Ewing’s sarcoma. An x-ray of the painful part of the bone is usually able to identify a tumour, although sometimes this can be difficult to see. Other tests are taken to check whether the cancer has spread elsewhere. These include a chest x-ray, bone scan, bone marrow aspirate, and an MRI or CT scan.

Any tests and investigations that your child needs will be explained to you. Our general information on children’s cancers, gives details of what the tests and scans involve.

Treatment will depend on a number of factors, including the size and position of the tumour, and may include chemotherapy, surgery and radiotherapy, or a combination of these.

Chemotherapy

Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. This is an important treatment for most children with Ewing’s sarcoma, and has greatly improved the results of surgical treatment. It is often given before surgery, and may shrink large tumours enough to avoid amputation. The course of chemotherapy will then continue after surgery, in order to destroy any remaining cancer cells and prevent the sarcoma from spreading outside the bone. Chemotherapy given in this way is called adjuvant chemotherapy.

Surgery

If surgery is needed, it may be carried out at a specialist orthopaedic centre. Often, surgery can remove the tumour without causing too much damage. If the tumour is in one of the main bones of the arm or leg, however, it may be necessary to remove the whole limb (amputation) or part of the affected bone. This is then replaced by some form of false limb (prosthesis). If only part of the affected bone is removed, this is known as limb-sparing surgery.

Amputation 

Amputation of the limb is sometimes unavoidable if the cancer has affected the surrounding blood vessels and nerves. After amputation, a false limb will be fitted, and this will be regularly adjusted as the child grows. False limbs can work very well. It should be possible for the child to join in with normal activities and even sport.

Limb-sparing surgery

There are several ways in which limb-sparing surgery may be done:

• replacing the bone with a prosthesis (a specially designed artificial part)
• replacing the bone with bone taken from another part of the body (a bone graft).

After limb-sparing surgery, the child is usually able to use the limb almost normally. However, it is best not to take part in any contact sports, as, if the bone graft or prosthesis is damaged, another major operation may be needed to repair or replace it. If the child is growing, a limb prosthesis will need to be lengthened from time to time as the bone grows. This will mean further short stays in hospital.

Radiotherapy

Radiotherapy treats cancer by using high-energy rays that destroy the cancer cells, while doing as little harm as possible to normal cells. Ewing’s sarcoma responds very well to radiotherapy and this treatment is often used after chemotherapy, and before or after surgery. If surgery is not possible (for example, if the tumour is in the spine) radiotherapy may be given instead of surgery.

Treatment often causes side effects, and your child’s doctor will discuss this with you before treatment starts. Any possible side effects will depend upon the actual treatment being used and the part of the body that is being treated. Side effects can include:

• feeling sick (nausea) and vomiting
• hair loss
• increased risk of infection
• bruising and bleeding
• tiredness
• diarrhoea

Late side effects

A small number of children may develop side effects, sometimes many years later. These include a possible reduction in normal bone growth, infertility, a change in the way the heart and lungs work, and a small increase in the risk of developing a second cancer in later life. Your child’s doctor or nurse will explain any possible late side effects.

More detailed information about the possible late side effects of treatment can be found in our general information on children's cancer.

Many children have their treatment as part of a clinical research trial. Trials aim to improve our understanding of the best way to treat an illness (usually by comparing the standard treatment with a new or modified version of the standard treatment). Specialist doctors carry out trials for children's cancer. Your child's medical team will talk to you about taking part in a clinical trial (if appropriate) and will answer any questions you may have. Written information is often provided to help explain things. Taking part in a research trial is completely voluntary and you'll be given plenty of time to decide if it is right for your child. Your child's doctor or specialist nurse can tell you more about this.

Most children with Ewing’s sarcoma can be cured. Even if the tumour comes back, further treatment may be given successfully. Surgery and radiotherapy can stop bones growing and may make muscles and tendons shorter. This may mean that further operations will be necessary later in life. However, most children who are successfully treated for Ewing’s sarcoma grow up without major disability.

If you have specific concerns about your child’s condition and treatment, it is best to discuss them with your child’s doctor, who knows the situation in detail.

As a parent, the fact that your child has cancer is one of the worst situations you can be faced with. You may have many different emotions, such as fear, guilt, sadness, anger and uncertainty. These are all normal reactions, and are part of the process that many parents go through at such a difficult time.

Your child may have a range of powerful emotions throughout their experience of cancer. Our booklet, Peppermint Ward, is a storybook for younger children with cancer. It looks at the issues that they and their family may face, and helps them to explore their feelings. You can order the booklet online.

This section has been compiled using information from a number of reliable sources, including:

• Cancer in Children: Clinical Management (5th ed). Eds PA Voute et al. Oxford University Press, 2005.

For further references, please see the general bibliography.